The Recovery of Mountains and Seas in Kyushu

A strange dream, a mysterious door, a bizarre world, what is named after mountains and seas, an ordinary boy who has been ordinary for more than ten years, why did he encounter these, is this world real? If not, what is the real world like? A strange encounter opened the curtain on everything. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.